Being able to click the auto-generate button to generate a synopsis from either the first lines or selected text in a document is very useful.
I would also find it useful if auto-generate could work in the opposite direction, for example:
Ctrl+auto-generate button = copy synopsis text to doc
Ctrl+Shift+auto-generate button = copy (prepend) synopsis text to beginning of doc, preserving current doc content
Ctrl+Shift+Alt+auto-generate button = copy (append) synopsis text to end of doc, preserving current doc content.